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1.
Adv Exp Med Biol ; 1169: 1-30, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31487016

RESUMO

In this chapter, heterogeneity is explored in the context of the ventricular-subventricular zone, the largest stem cell niche in the mammalian brain. This niche generates up to 10,000 new neurons daily in adult mice and extends over a large spatial area with dorso-ventral and medio-lateral subdivisions. The stem cells of the ventricular-subventricular zone can be subdivided by their anatomical position and transcriptional profile, and the stem cell lineage can also be further subdivided into stages of pre- and post-natal quiescence and activation. Beyond the stem cells proper, additional differences exist in their interactions with other cellular constituents of the niche, including neurons, vasculature, and cerebrospinal fluid. These variations in stem cell potential and local interactions are discussed, as well as unanswered questions within this system.


Assuntos
Encéfalo , Ventrículos Laterais , Células-Tronco Neurais , Nicho de Células-Tronco , Animais , Encéfalo/citologia , Linhagem da Célula , Ventrículos Laterais/citologia , Camundongos , Células-Tronco Neurais/citologia , Neurônios/citologia , Nicho de Células-Tronco/fisiologia
2.
Adv Exp Med Biol ; 1165: 253-283, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31399969

RESUMO

Renal fibrosis is characterized by excessive deposition of extracellular matrix (ECM), leading to destruction of normal kidney architecture and loss of renal function. The activation of α-smooth muscle actin-positive myofibroblasts plays a key role in this process. After kidney injury, profibrotic factors are secreted by injured tubular epithelia and infiltrated inflammatory cells to promote complex cascades of signaling events leading to myofibroblastic activation, proliferation, and ECM production. The origins of myofibroblasts remain controversial, and possibilities include resident fibroblasts, pericytes, bone marrow-derived cells, and endothelial cells. Recent evidence supports the existence of localized fibrogenic niches, which provides a specialized tissue microenvironment for myofibroblastic activation and expansion. Myofibroblasts often undergo epigenetic modifications, leading to their sustained activation and resistance to apoptosis. In this chapter, we discuss the origins, heterogeneity, and activation of myofibroblasts in diseased kidneys. We also highlight novel strategies for the treatment of patients with fibrotic kidney diseases.


Assuntos
Nefropatias/fisiopatologia , Miofibroblastos/citologia , Linhagem da Célula , Matriz Extracelular , Fibrose , Humanos , Rim/patologia
3.
Anticancer Res ; 39(8): 4055-4060, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31366487

RESUMO

BACKGROUND/AIM: Tumor-derived exosomes play important roles in tumor metastases. In this report, we observed the fate of tumor-derived exosomes in pancreatic cancer metastatic nude-mouse models using color-coded imaging. MATERIALS AND METHODS: Mia-PaCa-2 human pancreatic cancer cells expressing red fluorescent protein (RFP) were transduced by exosome-specific pCT-CD63-green fluorescent protein (GFP) and injected in the spleen of nude mice. RESULTS: Four weeks after injection of these cells into the spleen, liver metastases developed and tumor-derived exosomes were observed within the metastatic cancer cells and in Kupffer cells. Furthermore, tumor-derived exosomes diffused to bone marrow and lung cells, especially macrophages, without any metastases present. CONCLUSION: In the present study, we visualized the distribution of cancer-derived exosomes for the first time at the cellular level, in a pancreatic-cancer metastatic model.


Assuntos
Linhagem da Célula/genética , Exossomos/genética , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Pancreáticas/diagnóstico por imagem , Animais , Modelos Animais de Doenças , Proteínas de Fluorescência Verde/química , Humanos , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/secundário , Proteínas Luminescentes/química , Camundongos , Metástase Neoplásica , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Microambiente Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
4.
Nature ; 571(7765): 349-354, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31292549

RESUMO

Ascidian embryos highlight the importance of cell lineages in animal development. As simple proto-vertebrates, they also provide insights into the evolutionary origins of cell types such as cranial placodes and neural crest cells. Here we have determined single-cell transcriptomes for more than 90,000 cells that span the entirety of development-from the onset of gastrulation to swimming tadpoles-in Ciona intestinalis. Owing to the small numbers of cells in ascidian embryos, this represents an average of over 12-fold coverage for every cell at every stage of development. We used single-cell transcriptome trajectories to construct virtual cell-lineage maps and provisional gene networks for 41 neural subtypes that comprise the larval nervous system. We summarize several applications of these datasets, including annotating the synaptome of swimming tadpoles and tracing the evolutionary origin of cell types such as the vertebrate telencephalon.


Assuntos
Linhagem da Célula/genética , Ciona intestinalis/citologia , Ciona intestinalis/genética , Análise de Célula Única , Transcriptoma , Animais , Sequência de Bases , Evolução Biológica , Ciona intestinalis/classificação , Ciona intestinalis/crescimento & desenvolvimento , Gastrulação , Redes Reguladoras de Genes , Larva/citologia , Larva/genética , Sistema Nervoso/citologia , Sistema Nervoso/metabolismo , Neurônios/citologia , Neurônios/metabolismo , Notocorda/citologia , Notocorda/embriologia , Especificidade de Órgãos , Sinapses/genética , Sinapses/metabolismo
5.
Life Sci ; 232: 116652, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31302197

RESUMO

The development of new blood vessels from pre-existing vasculature is called angiogenesis. The growth of tumors depends on a network of supplying vessels that provide them with oxygen and nutrients. Pro-angiogenic factors that are secreted by tumors will trigger the sprouting of nearby existing blood vessels towards themselves and therefore researchers have developed targeted therapy towards these pro-angiogenic proteins to inhibit angiogenesis. However, certain pro-angiogenic proteins tend to bypass the inhibition. Thus, instead of targeting these expressed proteins, research towards angiogenesis inhibition had been focused on a deeper scale, epigenetic modifications. Epigenetic regulatory mechanisms are a heritable change in a sequence of stable but reversible gene function modification yet do not affect the DNA primary sequence directly. Methylation of DNA, modification of histone and silencing of micro-RNA (miRNA)-associated gene are currently considered to initiate and sustain epigenetic changes. Recent findings on the subject matter have provided an insight into the mechanism of epigenetic modifications, thus this review aims to present an update on the latest studies.


Assuntos
Linhagem da Célula , Epigenômica , Neoplasias/genética , Neoplasias/patologia , Metilação de DNA , Humanos
6.
Nat Commun ; 10(1): 2908, 2019 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-31266948

RESUMO

Cohesin and CTCF are master regulators of genome topology. How these ubiquitous proteins contribute to cell-type specific genome structure is poorly understood. Here, we explore quantitative aspects of topologically associated domains (TAD) between pluripotent embryonic stem cells (ESC) and lineage-committed cells. ESCs exhibit permissive topological configurations which manifest themselves as increased inter- TAD interactions, weaker intra-TAD interactions, and a unique intra-TAD connectivity whereby one border makes pervasive interactions throughout the domain. Such 'stripe' domains are associated with both poised and active chromatin landscapes and transcription is not a key determinant of their structure. By tracking the developmental dynamics of stripe domains, we show that stripe formation is linked to the functional state of the cell through cohesin loading at lineage-specific enhancers and developmental control of CTCF binding site occupancy. We propose that the unique topological configuration of stripe domains represents a permissive landscape facilitating both productive and opportunistic gene regulation and is important for cellular identity.


Assuntos
Fator de Ligação a CCCTC/química , Fator de Ligação a CCCTC/metabolismo , Elementos Facilitadores Genéticos , Células-Tronco Pluripotentes/metabolismo , Fator de Ligação a CCCTC/genética , Proteínas de Ciclo Celular/química , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Linhagem da Célula , Cromatina/química , Cromatina/genética , Cromatina/metabolismo , Proteínas Cromossômicas não Histona/química , Proteínas Cromossômicas não Histona/genética , Proteínas Cromossômicas não Histona/metabolismo , Células-Tronco Pluripotentes/química , Ligação Proteica , Domínios Proteicos , Especificidade da Espécie
7.
Nature ; 571(7765): 333-334, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31308528
8.
Nature ; 571(7765): 408-412, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31243370

RESUMO

Mutations in the transcription factor FOXA1 define a unique subset of prostate cancers but the functional consequences of these mutations and whether they confer gain or loss of function is unknown1-9. Here, by annotating the landscape of FOXA1 mutations from 3,086 human prostate cancers, we define two hotspots in the forkhead domain: Wing2 (around 50% of all mutations) and the highly conserved DNA-contact residue R219 (around 5% of all mutations). Wing2 mutations are detected in adenocarcinomas at all stages, whereas R219 mutations are enriched in metastatic tumours with neuroendocrine histology. Interrogation of the biological properties of wild-type FOXA1 and fourteen FOXA1 mutants reveals gain of function in mouse prostate organoid proliferation assays. Twelve of these mutants, as well as wild-type FOXA1, promoted an exaggerated pro-luminal differentiation program, whereas two different R219 mutants blocked luminal differentiation and activated a mesenchymal and neuroendocrine transcriptional program. Assay for transposase-accessible chromatin using sequencing (ATAC-seq) of wild-type FOXA1 and representative Wing2 and R219 mutants revealed marked, mutant-specific changes in open chromatin at thousands of genomic loci and exposed sites of FOXA1 binding and associated increases in gene expression. Of note, ATAC-seq peaks in cells expressing R219 mutants lacked the canonical core FOXA1-binding motifs (GTAAAC/T) but were enriched for a related, non-canonical motif (GTAAAG/A), which was preferentially activated by R219-mutant FOXA1 in reporter assays. Thus, FOXA1 mutations alter its pioneering function and perturb normal luminal epithelial differentiation programs, providing further support for the role of lineage plasticity in cancer progression.


Assuntos
Diferenciação Celular/genética , Fator 3-alfa Nuclear de Hepatócito/genética , Mutação , Fenótipo , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Sítios de Ligação , Linhagem da Célula , Cromatina/genética , Cromatina/metabolismo , Progressão da Doença , Regulação Neoplásica da Expressão Gênica , Fator 3-alfa Nuclear de Hepatócito/química , Humanos , Masculino , Camundongos , Camundongos Endogâmicos NOD , Motivos de Nucleotídeos , Organoides/citologia , Organoides/metabolismo
9.
Nature ; 571(7763): 112-116, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31189957

RESUMO

Size control is fundamental in tissue development and homeostasis1,2. Although the role of cell proliferation in these processes has been widely studied, the mechanisms that control embryo size-and how these mechanisms affect cell fate-remain unknown. Here we use the mouse blastocyst as a model to unravel a key role of fluid-filled lumen in the control of embryo size and specification of cell fate. We find that there is a twofold increase in lumenal pressure during blastocyst development, which translates into a concomitant increase in cell cortical tension and tissue stiffness of the trophectoderm that lines the lumen. Increased cortical tension leads to vinculin mechanosensing and maturation of functional tight junctions, which establishes a positive feedback loop to accommodate lumen growth. When the cortical tension reaches a critical threshold, cell-cell adhesion cannot be sustained during mitotic entry, which leads to trophectoderm rupture and blastocyst collapse. A simple theory of hydraulically gated oscillations recapitulates the observed dynamics of size oscillations, and predicts the scaling of embryo size with tissue volume. This theory further predicts that disrupted tight junctions or increased tissue stiffness lead to a smaller embryo size, which we verified by biophysical, embryological, pharmacological and genetic perturbations. Changes in lumenal pressure and size can influence the cell division pattern of the trophectoderm, and thereby affect cell allocation and fate. Our study reveals how lumenal pressure and tissue mechanics control embryo size at the tissue scale, which is coupled to cell position and fate at the cellular scale.


Assuntos
Diferenciação Celular , Linhagem da Célula , Embrião de Mamíferos/citologia , Embrião de Mamíferos/embriologia , Desenvolvimento Embrionário , Mecanotransdução Celular/fisiologia , Animais , Blastocisto/citologia , Adesão Celular , Divisão Celular , Forma Celular , Embrião de Mamíferos/anatomia & histologia , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Junções Íntimas , Vinculina/metabolismo
10.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 27(3): 942-949, 2019 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-31204959

RESUMO

OBJECTIVE: To understand the differentiation of mesoderm-derived Flk1+ cells on different locations of the early mouse embryonic development and to explore the potential of Flk1+ cells to differentiate into mesenchymal lineage, like pericytes during vascular development. METHODS: Based on the Cre-LoxP system conditional knockout study strategy, the Flk1-Cre mice and ROSA26 reporter mice were used for lineage-tracing studies. The fate of the Flk1+ progenitor cells was traced with the GFP+ population. The detection of mesoderm marker Flk1, hematopoietic cell-specific marker CD45, endothelial cell-specific markers CD31, CD144, and Emcn (endomucin), pericyte specific markers PDGFRß and NG2, using the methods of immunohistochemistry, immunofluorescence, and flow cytometry should be combined to solve the concerned problems. RESULTS: Immunohistochemical staining of different fractions of E8.5-10.5 in the early embryogenesis of Flk1-Cre; ROSA26-EYFP mouse lineage showed that there were multiple populations in the Flk1+ cell-derived GFP+ population surrounding hematopoietic sites, such as dorsal aortas, limb buds and yolk sac. In addition to hematopoietic cells, the CD31+/Emcn+ typical endothelial cells distributed specifically along the blood vessel wall, there were many types of cell populations, such as mesenchymal-like cells. The immunofluorescence demonstrated that the cells of this group are neither hematopoietic, non-endothelial cells around the blood vessels, which are NG2+ pericytes. FACS analysis also confirmed that Flk1+ cells contributed to pericytes. In addition, in different hematopoietic sites of the embryo, a small population of CD31+CD140B+ cell populations with a mesenchymal-like morphology was observed in the GFP+ population. CONCLUSION: In the early stages of embryogenesis, mesoderm-derived Flk1+ populations not only contribute to hematopoietic, endothelial, and muscle lineages, but also have a differentiation potential for mesenchymal lineage, like pericytes. The presumably observed CD31+CD140B+ cell population may be a group of endothelial cells differentiated from Flk1+ progenitor cells and undergoing an endothelium-to-mesenchymal transition, EndMT, gradually losing the endothelial surface-specific marker and also starting to express a pericyte surface-specific marker.


Assuntos
Linhagem da Célula , Mesoderma , Células-Tronco , Animais , Diferenciação Celular , Camundongos , Receptor 2 de Fatores de Crescimento do Endotélio Vascular , Saco Vitelino
11.
Nat Cell Biol ; 21(6): 674-686, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31160712

RESUMO

In vertebrates, multipotent progenitors located in the pharyngeal mesoderm form cardiomyocytes and branchiomeric head muscles, but the dynamic gene expression programmes and mechanisms underlying cardiopharyngeal multipotency and heart versus head muscle fate choices remain elusive. Here, we used single-cell genomics in the simple chordate model Ciona to reconstruct developmental trajectories forming first and second heart lineages and pharyngeal muscle precursors and characterize the molecular underpinnings of cardiopharyngeal fate choices. We show that FGF-MAPK signalling maintains multipotency and promotes the pharyngeal muscle fate, whereas signal termination permits the deployment of a pan-cardiac programme, shared by the first and second heart lineages, to define heart identity. In the second heart lineage, a Tbx1/10-Dach pathway actively suppresses the first heart lineage programme, conditioning later cell diversity in the beating heart. Finally, cross-species comparisons between Ciona and the mouse evoke the deep evolutionary origins of cardiopharyngeal networks in chordates.


Assuntos
Ciona intestinalis/genética , Coração/crescimento & desenvolvimento , Músculos Faríngeos/crescimento & desenvolvimento , Proteínas com Domínio T/genética , Animais , Diferenciação Celular/genética , Linhagem da Célula/genética , Ciona intestinalis/crescimento & desenvolvimento , Fatores de Crescimento de Fibroblastos/genética , Regulação da Expressão Gênica no Desenvolvimento/genética , Genômica , Mesoderma/crescimento & desenvolvimento , Camundongos , Quinases de Proteína Quinase Ativadas por Mitógeno/genética , Músculo Esquelético/crescimento & desenvolvimento , Músculo Esquelético/metabolismo , Miócitos Cardíacos/citologia , Miócitos Cardíacos/metabolismo , Fatores de Transcrição/genética
12.
Nat Cell Biol ; 21(6): 687-699, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31160711

RESUMO

We recently derived mouse expanded potential stem cells (EPSCs) from individual blastomeres by inhibiting the critical molecular pathways that predispose their differentiation. EPSCs had enriched molecular signatures of blastomeres and possessed developmental potency for all embryonic and extra-embryonic cell lineages. Here, we report the derivation of porcine EPSCs, which express key pluripotency genes, are genetically stable, permit genome editing, differentiate to derivatives of the three germ layers in chimeras and produce primordial germ cell-like cells in vitro. Under similar conditions, human embryonic stem cells and induced pluripotent stem cells can be converted, or somatic cells directly reprogrammed, to EPSCs that display the molecular and functional attributes reminiscent of porcine EPSCs. Importantly, trophoblast stem-cell-like cells can be generated from both human and porcine EPSCs. Our pathway-inhibition paradigm thus opens an avenue for generating mammalian pluripotent stem cells, and EPSCs present a unique cellular platform for translational research in biotechnology and regenerative medicine.


Assuntos
Diferenciação Celular/genética , Reprogramação Celular/genética , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes/citologia , Animais , Blastômeros/citologia , Blastômeros/metabolismo , Linhagem da Célula/genética , Células-Tronco Embrionárias/citologia , Camadas Germinativas/crescimento & desenvolvimento , Camadas Germinativas/metabolismo , Humanos , Camundongos , Medicina Regenerativa , Transdução de Sinais/genética , Suínos , Trofoblastos/citologia , Trofoblastos/metabolismo
13.
Nat Commun ; 10(1): 2787, 2019 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-31243281

RESUMO

Continuity, robustness, and regeneration of cell lineages relies on stem cell pools that are established during development. For the mammalian spermatogenic lineage, a foundational spermatogonial stem cell (SSC) pool arises from prospermatogonial precursors during neonatal life via mechanisms that remain undefined. Here, we mapped the kinetics of this process in vivo using a multi-transgenic reporter mouse model, in silico with single-cell RNA sequencing, and functionally with transplantation analyses to define the SSC trajectory from prospermatogonia. Outcomes revealed that a heterogeneous prospermatogonial population undergoes dynamic changes during late fetal and neonatal development. Differential transcriptome profiles predicted divergent developmental trajectories from fetal prospermatogonia to descendant postnatal spermatogonia. Furthermore, transplantation analyses demonstrated that a defined subset of fetal prospermatogonia is fated to function as SSCs. Collectively, these findings suggest that SSC fate is preprogrammed within a subset of fetal prospermatogonia prior to building of the foundational pool during early neonatal development.


Assuntos
Células-Tronco Germinativas Adultas/fisiologia , Linhagem da Célula , Testículo/embriologia , Animais , Diferenciação Celular , Desenvolvimento Embrionário , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Genes Reporter , Masculino , Camundongos , Camundongos Transgênicos , RNA/genética , Espermatogênese/fisiologia , Espermatogônias/fisiologia
14.
Opt Express ; 27(10): 13706-13720, 2019 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-31163830

RESUMO

An outstanding challenge for immunology is the classification of immune cells in a label-free fashion with high speed. For this purpose, optical techniques such as Raman spectroscopy or digital holographic microscopy have been used successfully to identify immune cell subsets. To achieve high accuracy, these techniques require a post-processing step using linear methods of multivariate processing, such as principal component analysis. Here we demonstrate for the first time a comparison between artificial neural networks and principal component analysis (PCA) to classify the key granulocyte cell lineages of neutrophils and eosinophils using both digital holographic microscopy and Raman spectroscopy. Artificial neural networks can offer advantages in terms of classification accuracy and speed over a PCA approach. We conclude that digital holographic microscopy with convolutional neural networks based analysis provides a route to a robust, stand-alone and high-throughput hemogram with a classification accuracy of 91.3 % at a throughput rate of greater than 100 cells per second.


Assuntos
Eosinófilos/citologia , Holografia/métodos , Redes Neurais (Computação) , Neutrófilos/citologia , Análise Espectral Raman/métodos , Linhagem da Célula , Separação Celular/métodos , Citometria de Fluxo , Humanos , Análise de Componente Principal
15.
Science ; 364(6444): 937-938, 2019 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-31171682
16.
Yakugaku Zasshi ; 139(6): 867-871, 2019.
Artigo em Japonês | MEDLINE | ID: mdl-31155527

RESUMO

The mesenchymal stem cell (MSC) is a type of tissue stem cell. In clinical studies, cultured MSCs have shown important therapeutic effects on diseases via both the reduction of neurological defects and the regulation of immune responses. However, in vivo MSC localization, function, and properties are poorly understood; therefore, the molecular understanding of MSC hierarchy is less advanced compared to hematopoietic stem cell hierarchy. Runt-related transcription factor 2 (Runx2) is an essential transcriptional regulator of osteoblast differentiation from MSCs. Runx2 deficiency in Paired-related homeobox 1 (Prrx1)-derived cells (Runx2Prrx1-/- mice) results in defective intramembranous ossification. Double-positive cells for Prrx1-GFP, and stem cell antigen-1 (Sca1) (Prrx1+Sca1+ cells) in the calvaria, express Runx2 at lower levels, and are more homogeneous and primitive compared with Prrx1+Sca1- cells. Our results suggest that osteoblast differentiation in vivo may begin at the Prrx1+Sca1+ MSC stage, with sequential progression to Prrx1+Sca1- cells, followed by Osterix+Prrx1-Sca1- osteoblast precursors, which eventually form mature α1(I)-collagen+ osteoblasts. This research will enable us to better understand the in vivo molecular biology features of MSCs, leading to their therapeutic applications for tissue repair and regeneration.


Assuntos
Linhagem da Célula , Descoberta de Drogas , Células-Tronco Mesenquimais , Camundongos/genética , Medicina Regenerativa , Animais , Diferenciação Celular , Subunidade alfa 1 de Fator de Ligação ao Core/fisiologia , Proteínas de Homeodomínio/fisiologia , Células-Tronco Mesenquimais/fisiologia , Biologia Molecular , Osteoblastos , Osteogênese/genética
17.
Nat Commun ; 10(1): 2395, 2019 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-31160568

RESUMO

Hematopoietic Stem/Progenitor cells (HSPCs) are endowed with the role of maintaining a diverse pool of blood cells throughout the human life. Despite recent efforts, the nature of the early cell fate decisions remains contentious. Using single-cell RNA-Seq, we show that existing approaches to stratify bone marrow CD34+ cells reveal a hierarchically-structured transcriptional landscape of hematopoietic differentiation. Still, this landscape misses important early fate decisions. We here provide a broader transcriptional profiling of bone marrow lineage negative hematopoietic progenitors that recovers a key missing branchpoint into basophils and expands our understanding of the underlying structure of early adult human haematopoiesis. We also show that this map has strong similarities in topology and gene expression to that found in mouse. Finally, we identify the sialomucin CD164, as a reliable marker for the earliest branches of HSPCs specification and we showed how its use can foster the design of alternative transplantation cell products.


Assuntos
Hematopoese/genética , Células-Tronco Hematopoéticas/metabolismo , Animais , Antígenos CD34/metabolismo , Células da Medula Óssea , Linhagem da Célula , Endolina/metabolismo , Perfilação da Expressão Gênica , Humanos , Camundongos , Análise de Sequência de RNA , Análise de Célula Única
18.
Nat Commun ; 10(1): 2400, 2019 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-31160565

RESUMO

BET-bromodomain inhibition (BETi) has shown pre-clinical promise for MYC-amplified medulloblastoma. However, the mechanisms for its action, and ultimately for resistance, have not been fully defined. Here, using a combination of expression profiling, genome-scale CRISPR/Cas9-mediated loss of function and ORF/cDNA driven rescue screens, and cell-based models of spontaneous resistance, we identify bHLH/homeobox transcription factors and cell-cycle regulators as key genes mediating BETi's response and resistance. Cells that acquire drug tolerance exhibit a more neuronally differentiated cell-state and expression of lineage-specific bHLH/homeobox transcription factors. However, they do not terminally differentiate, maintain expression of CCND2, and continue to cycle through S-phase. Moreover, CDK4/CDK6 inhibition delays acquisition of resistance. Therefore, our data provide insights about the mechanisms underlying BETi effects and the appearance of resistance and support the therapeutic use of combined cell-cycle inhibitors with BETi in MYC-amplified medulloblastoma.


Assuntos
Azepinas/farmacologia , Ciclo Celular/efeitos dos fármacos , Neoplasias Cerebelares/tratamento farmacológico , Meduloblastoma/tratamento farmacológico , Neurogênese/efeitos dos fármacos , Proteínas/antagonistas & inibidores , Triazóis/farmacologia , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/efeitos dos fármacos , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Sistemas CRISPR-Cas , Proteínas de Ciclo Celular/efeitos dos fármacos , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Linhagem da Célula , Neoplasias Cerebelares/genética , Ciclina D2/efeitos dos fármacos , Ciclina D2/metabolismo , Quinase 4 Dependente de Ciclina/antagonistas & inibidores , Quinase 6 Dependente de Ciclina/antagonistas & inibidores , Resistencia a Medicamentos Antineoplásicos , Perfilação da Expressão Gênica , Humanos , Meduloblastoma/genética , Camundongos , Células-Tronco Neurais/efeitos dos fármacos , Células-Tronco Neurais/metabolismo , Proteínas Proto-Oncogênicas c-myc/genética , Fase S/efeitos dos fármacos
19.
Nat Neurosci ; 22(6): 1021-1035, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31061494

RESUMO

While the roles of parenchymal microglia in brain homeostasis and disease are fairly clear, other brain-resident myeloid cells remain less well understood. By dissecting border regions and combining single-cell RNA-sequencing with high-dimensional cytometry, bulk RNA-sequencing, fate-mapping and microscopy, we reveal the diversity of non-parenchymal brain macrophages. Border-associated macrophages (BAMs) residing in the dura mater, subdural meninges and choroid plexus consisted of distinct subsets with tissue-specific transcriptional signatures, and their cellular composition changed during postnatal development. BAMs exhibited a mixed ontogeny, and subsets displayed distinct self-renewal capacity following depletion and repopulation. Single-cell and fate-mapping analysis both suggested that there is a unique microglial subset residing on the apical surface of the choroid plexus epithelium. Finally, gene network analysis and conditional deletion revealed IRF8 as a master regulator that drives the maturation and diversity of brain macrophages. Our results provide a framework for understanding host-macrophage interactions in both the healthy and diseased brain.


Assuntos
Encéfalo/citologia , Fatores Reguladores de Interferon/metabolismo , Macrófagos/citologia , Macrófagos/fisiologia , Animais , Diferenciação Celular/fisiologia , Linhagem da Célula/fisiologia , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microglia/citologia
20.
Nat Protoc ; 14(6): 1820-1840, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31110297

RESUMO

Fate mapping is a powerful genetic tool for linking stem or progenitor cells with their progeny, and hence for defining cell lineages in vivo. The resolution of fate mapping depends on the numbers of distinct markers that are introduced in the beginning into stem or progenitor cells; ideally, numbers should be sufficiently large to allow the tracing of output from individual cells. Highly diverse genetic barcodes can serve this purpose. We recently developed an endogenous genetic barcoding system, termed Polylox. In Polylox, random DNA recombination can be induced by transient activity of Cre recombinase in a 2.1-kb-long artificial recombination substrate that has been introduced into a defined locus in mice (Rosa26Polylox reporter mice). Here, we provide a step-by-step protocol for the use of Polylox, including barcode induction and estimation of induction efficiency, barcode retrieval with single-molecule real-time (SMRT) DNA sequencing followed by computational barcode identification, and the calculation of barcode-generation probabilities, which is key for estimations of single-cell labeling for a given number of stem cells. Thus, Polylox barcoding enables high-resolution fate mapping in essentially all tissues in mice for which inducible Cre driver lines are available. Alternative methods include ex vivo cell barcoding, inducible transposon insertion and CRISPR-Cas9-based barcoding; Polylox currently allows combining non-invasive and cell-type-specific labeling with high label diversity. The execution time of this protocol is ~2-3 weeks for experimental data generation and typically <2 d for computational Polylox decoding and downstream analysis.


Assuntos
Linhagem da Célula , Genes Reporter , Análise de Sequência de DNA/métodos , Animais , Sistemas CRISPR-Cas , DNA/genética , DNA/metabolismo , Código de Barras de DNA Taxonômico/métodos , Feminino , Técnicas de Genotipagem/métodos , Integrases/genética , Masculino , Camundongos , Camundongos Transgênicos , Reação em Cadeia da Polimerase/métodos , Recombinação Genética
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